The present disclosure relates generally to an imaging module and a system for, and a method of, directing an aiming pattern on, and illuminating, a target to be electro-optically read by image capture during operation of an imaging reader, and more particularly, to a hybrid aiming/illuminating assembly for aiming the reader at, and illuminating, the target during the operation of the reader.
Solid-state imaging systems or imaging readers have been used, in both handheld and/or hands-free modes of operation, to electro-optically read targets, such as one- and two-dimensional bar code symbol targets, and/or non-symbol targets, such as documents. A handheld imaging reader includes a housing having a handle held by an operator, and an imaging module, also known as a scan engine, supported by the housing and aimed by the operator at a target during reading. The imaging module includes a solid-state imager or imaging sensor with an array of photocells or light sensors, which correspond to image elements or pixels in an imaging field of view of the imager, and an imaging lens assembly for capturing return light scattered and/or reflected from the target being imaged, and for projecting the return light onto the array to initiate capture of an image of the target. Such an imager may include a one- or two-dimensional charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) device and associated circuits for producing and processing electronic signals corresponding to a one- or two-dimensional array of pixel data over the imaging field of view.
In order to increase the amount of the return light captured by the array, especially in dimly lit environments and/or at far range reading, the imaging module generally also includes an illuminating light assembly for illuminating the target with illumination light over an illumination field or illumination light pattern for reflection and scattering therefrom. The illumination light pattern is typically generated by using an illuminating light source, e.g., one or more light emitting diodes (LEDs), and one or more sets of illuminating lenses.
In addition, to alleviate the problem that the operator cannot readily tell whether the reader is aimed directly at the target, which can be located anywhere within a range of working distances away from the reader, the imaging module generally also includes an aiming light assembly to provide visual feedback to the operator to advise where the reader is aimed. The known aiming light assembly utilizes at least one aiming light source, e.g., a laser, for generating an aiming beam, and an aiming element, including, for example, a diffractive optical element (DOE), or a refractive optical element (ROE), for focusing and optically modifying the aiming beam to direct a visible aiming light pattern, e.g., a spot, a line, or a cross-hairs, on the target prior to reading.
The use of a separate aiming light assembly and a separate illuminating light assembly increases the overall size, complexity and cost of manufacturing and assembling the imaging module and the reader. Also, the light sources of these separate assemblies have to each be electrically powered, and this extra power requirement undesirably drains an on-board battery typically provided in handheld, wireless imaging readers, thereby requiring more frequent recharging, more downtime, and shorter working lifetimes.
Accordingly, there is a need to reduce the size, complexity and cost of manufacturing and assembling the imaging module and the reader, and to make the imaging module and the reader more energy-efficient.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and locations of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The system and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.